Numerical Investigations of Tsunami Run-Up and Flow Structure on Coastal Vegetated Beaches
Abstract
:1. Introduction
2. Numerical Method
2.1. Governing Equations
2.2. Vegetation Drag Force
2.3. Finite Volume Method
2.4. Evaluation of Numerical Fluxes
2.5. Treatment of Wetting and Drying Fronts
- Wet edge (see Figure 1a): two adjacent cells are wet, in which water depth of left cell hL > ε and water depth of right cell hR > ε.
- Partially wet edge (with flux), as presented in Figure 1b: a wet cell (left) links to a dry cell on the right, and the water level of the wet cell is higher than that of the dry cell, where hL > ε, hR ≤ ε and water level of left cell ηL > water level of left cell ηR.
- Partially wet edge (no flux), as shown in Figure 1c: a wet cell (left) links to a dry cell on the right, and the water level of the wet cell is lower than that of the dry cell, where hL > ε, hR ≤ ε, and ηL < ηR. To eliminate the non-physical flux problem produced in the interface, the water level ηR and bed level ZbR for the dry cell were temporarily replaced by a value which equaled to the water level ηL in the wet cell.
- Wet cell: all the edges of this cell consisted of a wet or partially wet edges (with flux) and all the nodes of the cell are flooded.
- Dry cell: all the edges of this cell consist of dry or partially wet edges (no flux).
- Partially wet cell: all other cells do not satisfy the criteria of either a wet or dry cell, as defined above.
3. Numerical Simulation and Experimental Validation
3.1. Solitary Wave Run-up on a Bare Sloping Beach
3.2. Propagation of Long Periodic Waves on a Partially Vegetated Sloping Beach
3.3. Effects of Forest on Tsunami Run-up at Actual Scale
3.3.1. Coastal Topography and Forest Conditions
3.3.2. Effects of Forest with a Straight Open Gap on Tsunami Run-up
3.3.3. Effects of Arrangements of Vegetation Patches and Open Gaps
3.3.4. Effects of Forest Parameters on Tsunami Run-up
4. Conclusions
Author Contributions
Funding
Conflicts of Interest
References
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Zhang, H.; Zhang, M.; Xu, T.; Tang, J. Numerical Investigations of Tsunami Run-Up and Flow Structure on Coastal Vegetated Beaches. Water 2018, 10, 1776. https://doi.org/10.3390/w10121776
Zhang H, Zhang M, Xu T, Tang J. Numerical Investigations of Tsunami Run-Up and Flow Structure on Coastal Vegetated Beaches. Water. 2018; 10(12):1776. https://doi.org/10.3390/w10121776
Chicago/Turabian StyleZhang, Hongxing, Mingliang Zhang, Tianping Xu, and Jun Tang. 2018. "Numerical Investigations of Tsunami Run-Up and Flow Structure on Coastal Vegetated Beaches" Water 10, no. 12: 1776. https://doi.org/10.3390/w10121776